fix(indexer): prevent token exhaustion and reserve 20% budget for website users

- Lower exhaustion threshold from <10 to <2 (stop wasting remaining tokens)
- Refresh ALL tokens after wait instead of only one
- Fix token/Octokit mismatch by returning token from getBestInstance()
- Add budget checking (20% reserve) to deep-scan, discover-repos, awesome-lists,
  and full-enhanced commands
- Add rate limit error handling with retry in DeepScanCrawler
- Sync translation and query changes

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

apps/web/messages/en.json

@@ -33,7 +33,7 @@
     "docs": "Docs",
     "about": "About",
     "github": "GitHub",
-    "sourceCode": "Source Code (Coming Soon)",
+    "sourceCode": "Source Code",
     "sourceCodeShort": "Source Code",
     "switchLanguage": "Switch to Farsi"
   },
@@ -203,7 +203,7 @@
       "attribution": "Attribution",
       "manageSkills": "Manage Skills"
     },
-    "sourceCode": "Source Code (Coming Soon)",
+    "sourceCode": "Source Code",
     "copyright": "© {year} SkillHub. Open source under MIT license."
   },
   "about": {